Flexible shaft and casing



1938. A. WYZENBEEK FLEXIBLE SHAFT AND CASING March 22,

Filed Feb. 20, 1957 Patented Mar. 22, 1938 .UNITED: STATES PATENT QFFICE FLEXIBLE SHAFT AND CASING Andrew-Wyzenbeek, Chicago, Ill. Application February 20, 1937, Serial No. 126,920

9 Claims. (Cl. 54-4) This invention relatessto a flexible shaft and a' sectional view taken as indicated at line 2-2 casing anddealswith the type of shaft which is of Fig. 1.

adapted to rotate while maintaining a curved The flexible shaftAcomprises awire closely form and which is used to transmit torque in a coiled'into the form of a. tube. When free'and 5 curved .path. unrestricted, the shaft is straight and of cylin- 5 An object of i the invention is to provide a drical form, but it may be easily bent into curved shaftiand a tubular enclosure in which the shaft 7 form and may be easily turned while held in may rotatecfreely though in curved Jform, and this curved form; Atits one end shaft A is conwhich'does not become unduly worn or deterinected to some means suchas short shaft Ill by l -orated. throughxcontact 1, of the shaft with its which a torque may be delivered-to this end'lO casing." of the shaft A; Similar means a. may be pro- Another ob-jectis to provide an'enclosure for videdatits other end for receiving the torque the flexible 'shaft which resists wear and prodelivered by the shaft A'or,'if desired, the other videsthe necessary rigidity,but=which will not end may be connected directly to the appliance lafiect'the properties of the shaft through conwhich is-to be rotated. The coiled type of shaft, tacttherewith even after. prolonged use. Other as here shown, has-definite advantages when the more specific objects will appear as thespecificatorque to be transmitted'is-all in the same angution proceeds. lar direction. With the wire coiled as shown in A flexible rotatableshaft 'is often employed to the illustration. aclockwise torque applied to the transmit power, and one of its characteristic adshort shaft Ill-would tend to-bring each of the vantages is that it need notbestraight, but canbe tu ns of the coil into 'contact with each other curved in any desired form, as the situation may and the elfect would be much the same as in require. The shaft is ordinarily encasedin a tube the case of a straight h 0W"l3 er However, which restricts its form and provides a channel other types of fiexibleshafts may be employed 135, in which it may rotate. Because therotating w sodesired- The Casing -thaf A Comshaft is'in contact with the inside wallof the prises the armor H which is'in theform of a a in .11; ha b necessarynto ma,ke th i metallic strip coiled 'in'the form of atube. It side of the tubular casing of a firm wear-resi t is desirable that this armor be rather loosely ing material, and a material which meets this 6011611160 thatlit ayb e fleXible and'the 3Iequi1ement'hasbeen found 'in metal armor. In casing may bent moreeasilyl outsideiaifmor 0 r the past a metal strip coiled to form a tube has II is a ye o rubb r l2 which is in close conbeen used on the inside of the enclosure and in t W ht e tu ns of armor II and tends to contact with the rotatable shaft, and such has resiliently 110101 t in p ope p s o 0111?- been satisfactory so -far as rigidity and wear side rubber layer I2 is a fabric layer l3 and over resisting qua]ities are concerned, this is a loosely coiled metal strip I4 forming an 35 However, after the shaft h b d for outer armor. The fabric [3 and. its outer armor some t in t b having an inside wall of M form asubstantial support for the inner strucmetallic armor, the shaft has a definite tendtllre and do not appreciably pa t e flexibilarmy t crystallize and after t onstaiiizaity of the tube. If desired, another metal strip t has gone forward t some jgtnt t haft I5 may be coiled about the exterior of the casing 40 will break and must be replaced. Heretofore it to f as a guardhas been thought that the crystallization was P the m armor proYlde tubular due to the constant bending of the shaft while hmng Whlch 15 formed by coihng strip of in use and could not be avoided. I have found, Y t fibre into t .form 9 tube The however, that this tendency to crystallize can 2 gf i the llslde of be avoided by interposing between the metallic an 5 18 S 6 me .armor Contact Wlth armor and the metallic flexible shaft a lining of the Shaft" The vulcamzed fibre 1S fibrous terial which has been treated with rubber and is vulcamzed fibre. The specific structure of my a well-known product. This material, while plilmproved shaft and tube W111 appeal: more a able enough to be sufficiently flexible as here 50 ly brreference to the accompanyme w s, used, is very tough and easily resists the wear 1n Wh10h to which it is subjected. Other tough and non- Fig. l is a broken plan viewof the shaft and metallic materials may also be used to form this tube, the parts and coverings being sufficiently lining, if desired. Lining I6 is preferably coiled 5 broken away to show its structure; and Fig. 2, rather loosely as illustrated in Fig. 1, to increase its flexibility. Also, it is preferable that this lining be coiled in a direction opposite that of the flexible coiled shaft. By having the fibre lining coiled in a direction opposite that of the flexible shaft the tendency of the wire of the shaft to catch upon the edges of the fibre strip as the shaft turns is avoided.

At the ends of the casing bearings l1 may be provided and the short shafts Ill journaled in these bearings so as to relieve the flexible shaft of any unnecessary strain. In Fig. 1 only one end of the shaft and casing is shown but it is understood that the other end may be similarly equipped and adapted.

In the use of my improved shaft and easing the flexible shaft A rotates within the lining l6 and the lining frictionally engages the shaft to maintain it in position. The rubbing of the shaft against the vulcanized fibre lining does not affect in any way the physical properties of the shaft and the crystallization common in ordinary structures is altogether eliminated here.

While in the above description I have set forth a single embodiment of a specific structure as illustrative of my invention, it will be understood that many changes can be made therein without departing from the spirit of my invention. The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible in view of the prior art.

What I claim as new and desire to secure by Letters Patent is:

1. Apparatus of the character set forth, comprising a flexible metallic shaft adapted to rotate while maintaining a curved form, a flexible metallic casing about said shaft, and a non-metallic lining within said metallic casing, said lining being effective to prevent said shaft from coming into contact with said casing.

2. In combination with a flexible metallic shaft enclosed in a casing, a fibre lining within said casing and about said shaft.

3. Apparatus of the character set forth, comprising a flexible metallic hollow shaft, a metallic casing about said shaft, and a treated fibre lining within said casing and in contact with said shaft.

4. Apparatus of the character set forth, comprising a flexible metallic shaft adapted to rotate while maintaining a curved form, a tubular casing about said shaft comprising a coil of metallic armor, and a fibre lining within said casing and in contact with said shaft, said lining comprising a strip of vulcanized fibre material coiled into tubular form.

5. Apparatus of the character set forth, comprising: a flexible metallic shaft adapted to rotate while maintaining a curved form; a tubular casing about said shaft comprising an inner layer of coiled metallic armor and layers of rubber and fabric enclosing said coiled armor, and a lining of fibre within said casing and about said shaft, said lining comprising a strip of flbre coiled into tubular form.

6. Apparatus of the character set forth, comprising: a wire coiled to provide a flexible shaft, and adapted to rotate while maintaining a curved form; a casing about said shaft, said casing enclosing the coiled metallic strip forming a tubular armor; a treated fibre lining within said casing and about said shaft; and bearings secured to the ends of said casing, said shaft being journaled in said bearings.

7. Apparatus of the character set forth, comprising: a wire coiled to provide a flexible shaft, said shaft being adapted to receive a torque at one end and deliver said torque at its other end While maintaining a curved form; a casing about said shaft including an inner metallic armor, rubber and fabric layers over said inner armor, a non-metallic lining within said casing and about said shaft, said lining having a smooth inside surface, and an outer armor about said rubber and fabric layers; and a bearing secured to an end of said casing, said shaft being journaled in said bearing.

8. Apparatus of the character set forth, comprising: a flexible metallic shaft adapted to rotate while maintaining a curved form, a casing about said shaft, and a lining between said shaft and said casing, said lining being of hard non-metallic material having a smooth inside surface.

9. Apparatus of the character set forth, comprising: a flexible metallic shaft adapted to rotate while maintaining a curved form, a casing about said shaft comprising a coil of metallic armor, and lining comprising a coil of hard non-metallic material having a smooth inside surface.

ANDREW WYZENBEEK. 

